Home battery storage: capacity, power, and profitability

Selecting a home battery system requires balancing capacity (kWh) with discharge power (kW). While capacity determines how much energy is stored, power determines whether the battery can support high-demand appliances like induction cooktops or electric vehicle chargers. Experts suggest analyzing a household's specific daily energy profile—including seasonal variations and the presence of heat pumps or electric vehicles—rather than relying on general rules of thumb.

In terms of financial viability, large fixed home batteries from providers such as Quatt, Tibber, Zonneplan, Sigenergy, and AlphaESS are currently being used to trade on the energy market by charging during low-price periods and discharging during peaks. Real-world examples show significant returns; for instance, a 22 kWh Quatt battery earned approximately 1,950 euros in 11 months, suggesting a potential payback period of roughly 2.6 years. However, questions remain regarding the long-term profitability of these systems after January 1, 2027, when energy market trading incentives may change.